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1.
Polymers (Basel) ; 12(6)2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32580298

RESUMO

The transdermal delivery of therapeutic agents amplifying a local concentration of active molecules have received considerable attention in wide biomedical applications, especially in vaccine development and medical beauty. Unlike oral or subcutaneous injections, this approach can not only avoid the loss of efficacy of oral drugs due to the liver's first-pass effect but also reduce the risk of infection by subcutaneous injection. In this study, a magneto-responsive transdermal composite microneedle (MNs) with a mesoporous iron oxide nanoraspberry (MIO), that can improve the drug delivery efficiency, was fabricated by using a 3D printing-molding method. With loading of Minoxidil (Mx, a medication commonly used to slow the progression of hair loss and speed the process of hair regrowth), MNs can break the barrier of the stratum corneum through the puncture ability, and control the delivery dose for treating androgenetic alopecia (AGA). By 3D printing process, the sizes and morphologies of MNs is able to be, easily, architected. The MIOs were embedded into the tip of MNs which can deliver Mx as well as generate mild heating for hair growth, which is potentially attributed by the expansion of hair follicle and drug penetration. Compared to the mice without any treatments, the hair density of mice exhibited an 800% improvement after being treated by MNs with MF at 10-days post-treatment.

2.
Spine (Phila Pa 1976) ; 39(22): 1850-9, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25077906

RESUMO

STUDY DESIGN: Retrospective radiographical review. OBJECTIVE: To demonstrate that the structural and noncompensatory Lenke 3 and 4C lumbar curves could be nonstructural and compensatory. SUMMARY OF BACKGROUND DATA: Historically, Lenke 3 and 4C curves were not recommended for selective thoracic fusion (STF) because the lumbar curve was considered structural and noncompensatory. However, consecutive series of Lenke 3 and 4C curves suggest successful treatment with STF. METHODS: Between 2001 and 2004, 2005 and 2008, and 2010 and 2012, 3 consecutive series of 108, 134, and 78 surgically treated Lenke 1, 2, 3, and 4C curves were reviewed, respectively. The coronal curve criteria for the curves treated with STF during each period were lumbar side bending Cobb angle less than 25° and meeting the Lenke ratio criteria, lumbar side bending Cobb angle 35° or less, and lumbar side bending Cobb angle 45° or less, respectively. The sagittal curve criteria for STF during each period was absence of junctional thoracolumbar kyphosis 20° or more between T10 and L2. The technique used for STF was the Guan-Din method. Radiographs of all the curves treated with STF were analyzed before and after surgery. RESULTS: Optimal instrumented thoracic and compensatory lumbar correction was obtained for all Lenke 1, 2, 3, and 4C curves treated with STF in each period. As the coronal criteria for STF were broadened, the extent of feasibility of STF was expanded and the rate of STF increased. Although Cobb angle, apical vertebral translation, and apical vertebral rotation magnitudes of Lenke 3 and 4C curves were larger and more severe than those of Lenke 1 and 2C curves, optimal compensatory correction could still be obtained for Lenke 3 and 4C curves. CONCLUSION: The structural and noncompensatory Lenke 3 and 4C lumbar curves were proven to be nonstructural and compensatory. Lenke 1, 2, 3, and 4C curves have similar natures and similar responses to the same technique (Guan-Din method) used for STF and could be considered collectively as a single indication for STF. The extent of feasibility of STF could be expanded from Lenke 1 and 2 curves to Lenke 1, 2, 3, and 4 curves. LEVEL OF EVIDENCE: 2.


Assuntos
Vértebras Lombares/diagnóstico por imagem , Curvaturas da Coluna Vertebral/diagnóstico por imagem , Curvaturas da Coluna Vertebral/cirurgia , Fusão Vertebral , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Adolescente , Feminino , Humanos , Vértebras Lombares/fisiopatologia , Masculino , Seleção de Pacientes , Radiografia , Estudos Retrospectivos , Curvaturas da Coluna Vertebral/classificação
3.
Spine (Phila Pa 1976) ; 39(4): E284-93, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24553450

RESUMO

STUDY DESIGN: Retrospective radiographical review. OBJECTIVE: To evaluate the outcome of selective thoracic fusion (STF) by using the Guan-Din method for the treatment of major thoracic compensatory lumbar (MTCL) curves. SUMMARY OF BACKGROUND DATA: Performing STF for MTCL curves is to minimize the loss of lumbar motion and the risk of lumbar degeneration or pain. Surgical treatment of MTCL curves aims to maximize the rate of STF for MTCL curves while optimizing instrumental thoracic and compensatory lumbar correction. The Guan-Din method has been demonstrated to be able to enhance the lumbar curve's capacity for spontaneous correction and broaden the current curve criteria of MTCL curves for STF. METHODS: Between 2004 and 2010, 510 consecutive surgically treated MTCL curves were reviewed. Of these MTCL curves, who met the criteria of lumbar side bending Cobb 35° or less and without global thoracic hyperkyphosis and/or thoracolumbar kyphosis (T10-L2 ≤20°), were treated with STF using the Guan-Din method. Radiographs were analyzed before surgery, immediately after surgery, and at the most recent follow-up (range, 2-8 yr). RESULTS: Curve types of 510 MTCL curves according to Lenke system were as follows: 1A (n = 91), 2A (n = 74), 3A (n = 6), 4A (n = 2), 1B (n = 93), 2B (n = 34), 3B (n = 8), 4B (n = 5), 1C (n = 84), 2C (n = 26), 3C (n = 72), and 4C (n = 15). Of the 510 MTCL curves, 458 (90%) curves were treated with STF. A mean 73% thoracic correction and 63% lumbar correction was obtained at the most recent follow-up. Of the 197 surgically treated MTCL curves with a lumbar C modifier, 148 (75%) curves that contained 57 Lenke 1C and 2C curves and 40 Lenke 3C and 4C curves that did not meet Lenke curve criteria for STF, were successfully treated with STF. A mean 67% thoracic correction and 57% lumbar correction was obtained at the most recent follow-up. The rate of STF and the magnitude of correction of MTCL curves in this study were significantly greater than those in all other reports. No significant change in global coronal and sagittal imbalance was observed. CONCLUSION: The rate of STF and the compensatory correction of MTCL curves could be maximized by using the Guan-Din method as the method for STF. LEVEL OF EVIDENCE: 4.


Assuntos
Escoliose/cirurgia , Fusão Vertebral/métodos , Vértebras Torácicas/cirurgia , Adolescente , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Radiografia , Estudos Retrospectivos , Escoliose/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Resultado do Tratamento , Adulto Jovem
4.
J Spinal Disord Tech ; 25(3): E67-73, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22124422

RESUMO

STUDY DESIGN: Retrospective. OBJECTIVE: To evaluate the clinical safety and accuracy of the Tai Chi ((Equation is included in full-text article.)) technique for placing pedicle screws, without intraoperative radiographic imaging, in severe scoliotic spines. SUMMARY OF BACKGROUND DATA: The current techniques for pedicle screw placement have a number of drawbacks in cases of severe scoliosis, including difficulty or impossibility to use, delayed operative time, requiring the presence of trained personnel for the duration of the surgery, high cost issues, increased radiation exposure, and technical challenges. No previous report has described the application of the Tai Chi pedicle screw placement technique for severe scoliosis. MATERIAL AND METHODS: Between 2006 and 2008, the cases of 39 consecutive patients with severe scoliosis (Cobb angle >100 degrees) who underwent posterior correction and stabilization (from T1 to L5) using 992 transpedicular screws were examined. The mean patient age was 25.7 (range, 11 to 63) years at the time of surgery. Pedicle screws were inserted by the Tai Chi technique using anatomic landmarks and preoperative radiographs as a guide. Tai Chi drilling fully utilizes the natural anatomic and physical characteristics of pedicles and unconstrained circular force. By nature, a drill bit driven by unconstrained circular force would migrate within the pedicle along a path of least resistance, advancing along the central cancellous bone tunnel spontaneously. Accurate drilling was achieved by following the nature and sticking to the hand sensation when the drill bit broke through the cancellous bone. The total time for inserting all pedicle screws in each case was recorded. Postoperative computed tomography scans were performed to evaluate the position of the inserted pedicle screws. The screw position was classified as "in" or "out." The distance of perforation was measured. RESULT: The average Cobb angle was 127 degrees (range, 100 to 153 degrees). The number of screws inserted at each level were as follows: T1 (n=10), T2 (n=34), T3 (n=46), T4 (n=53), T5 (n=61), T6 (n=69), T7 (n=75), T8 (n=76), T9 (n=76), T10 (n=77), T11 (n=76), T12 (n=78), L1 (n=77), L2 (n=68), L3 (n=56), L4 (n=38), and L5 (n=22). There were 923 (93%) "in" screws and 69 (7%) "out" screws. The overall accuracy of screw placement was 93%. There were no neurological, vascular, or visceral complications. No screws required postoperative repositioning. The average time for pedicle screw placement was 73 seconds. CONCLUSIONS: Our findings suggest that the Tai Chi pedicle screw placement technique, which does not require intraoperative radiographic imaging, is an accurate, reliable, safe, and time-saving method of placing pedicle screws in severe scoliotic spines.


Assuntos
Parafusos Ósseos , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Fusão Vertebral/instrumentação , Fusão Vertebral/métodos , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Implantação de Prótese/métodos , Radiografia , Tai Chi Chuan , Resultado do Tratamento , Adulto Jovem
5.
Spine (Phila Pa 1976) ; 36(20): 1658-64, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21358573

RESUMO

STUDY DESIGN: Retrospective radiographic review. OBJECTIVE: To evaluate the outcome of selective thoracic fusion (STF) by using cantilever bending technique (CBT) and the direct vertebral rotation (DVR) technique for major thoracic-compensatory lumbar (MTCL) curves selected by new curve criteria, which are broader than Lenke curve criteria for STF. SUMMARY OF BACKGROUND DATA: Surgical treatment of MTCL curves aims to maximize the number of MTCL curves that can be treated with STF and optimize instrumented thoracic and spontaneous lumbar correction. Comparing current guidelines for STF shows that the surgical technique utilized for STF may affect the curve criteria for MTCL curves for successful STF and thoracic and lumbar correction. METHODS: Seventy-eight consecutive idiopathic scoliosis patients with major thoracic-compensatory "C" modifier lumbar curves who met the following three criteria: (1) main thoracic curve (MT) to compensatory lumbar curve (CL) ratios of Cobb magnitude and apical vertebral translation (AVT) greater than one; (2) MT/CL ratio of flexibility less than one; (3) Cobb magnitude of lumbar curve less than 35° on side bending, were treated with STF by using CBT and DVR. Radiographs were analyzed before surgery, immediately after surgery, and at the most recent follow-up (range, 2-5 years). RESULTS: All 78 MTCL curves were successfully treated with STF by using CBT and DVR. A mean 61% thoracic correction was matched by 55% lumbar correction at the most recent follow-up. Spontaneous correction of lumbar AVT occurred in all patients. Global coronal imbalance was common before surgery (mean, 14 mm) and remained so after surgery (mean, 12 mm). There were 49 MTCL curves that did not meet Lenke curve criteria for STF. All were successfully treated with STF by using CBT and DVR. Among these 49 MTCL curves, there were 14 Lenke 1C and 18 Lenke 2C curves with one or two, or all of MT/CL ratios of Cobb magnitude, AVT, and apical vertebral rotation of 1.2 or less, and 6 Lenke 3C and 11 Lenke 4C curves with the Cobb magnitude of residual lumbar curve on side bending between 25° and 35°. CONCLUSION: CBT and DVR can broaden the current curve criteria of MTCL curves for STF to have more MTCL curves treatable with STF and optimize instrumented thoracic and spontaneous lumbar correction. A more effective surgical technique can not only improve instrumented thoracic and spontaneous lumbar correction but also can broaden the MTCL curve criteria for STF to have more MTCL curves treatable with STF.


Assuntos
Vértebras Lombares/cirurgia , Implantação de Prótese/métodos , Escoliose/cirurgia , Fusão Vertebral/métodos , Vértebras Torácicas/cirurgia , Adolescente , Adulto , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Masculino , Radiografia , Estudos Retrospectivos , Escoliose/diagnóstico por imagem , Escoliose/patologia , Fusão Vertebral/instrumentação , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/patologia , Adulto Jovem
6.
Spine (Phila Pa 1976) ; 36(3): E186-97, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21242882

RESUMO

STUDY DESIGN: Prospective radiographic study. OBJECTIVE: To investigate the feasibility of controlling quality of reconstructed sagittal balance for sagittal imbalance. SUMMARY OF BACKGROUND DATA: Patients with sagittal imbalance cannot walk or stand erect without overwork of musculature because of compromised biomechanical advantage. The result is muscle fatigue and activity-related pain. During reconstructive surgery, restoration of optimal sagittal balance is crucial for obtaining satisfactory clinical results. However, there is no way to control quality of reconstructed sagittal balance before or during surgery. METHODS: A method was developed to determine the lumbosacral curve in a way that theoretically would bring sagittal balance to an ideal state by calculation and simulation for each patient before surgery and then template rods of the curve and a blueprint were made accordingly for operative procedures. Ninety-four consecutive patients with sagittal imbalance due to lumbar kyphosis were treated for intractable pain and then followed up for a mean of 4.3 years. Radiographs were analyzed before surgery, 2 months after surgery, and at most recent follow-up. RESULTS: The mean estimated values of L1-S1 lordosis, sacral inclination angle, sacrofemoral distance, and distribution of L1-S1 lordosis at the closing-opening wedge osteotomy site and L4-S1 segments were 30.8°, 24.6°, 0 mm, 16.1% (-5°), and 62% (-19°), respectively. The mean reconstructed values were 41.1°, 23.3°, 3.9 mm, 41% (-17°), and 46% (-19°), respectively. There were significant differences between estimated and reconstructed values of L1-S1 lordosis and the percentage of distributions; however, there was no significant difference between the estimated and reconstructed magnitude of L4-S1 lordosis, sacral inclination angle, and sacrofemoral distance. A properly oriented pelvis can be brought nearly directly above the hip axis. The mean sagittal global balance, represented by the distance between the vertical line through the hip axis and sacral promontory, improved from 61.4 mm before surgery to 3.9 mm 2 months after surgery, and 1.3 mm at final follow-up. Normal sagittal global balance was reconstructed and maintained. The mean sagittal spinal balance measured as the horizontal distance between the C7 sagittal plumb line and the posterior superior corner of S1 improved from 97.4 mm before surgery to 11 mm 2 months after surgery. However, there was significant loss of sagittal spinal balance to 25.4 mm at the fi nal visit. Normal sagittal spinal balance was reconstructed and appeared to be maintained. The magnitude of T1-T12 kyphosis compensated from 13° before surgery to 25.2° 2 months after surgery and 34.5° at fi nal follow-up. CONCLUSIONS: Quality control of the reconstructed sagittal balance for sagittal imbalance is possible. Correctly orienting the pelvis, reconstructed by the restoration of enough L1-S1 lordosis with adequate distribution at L4-S1 segments, is a matter of critical importance for optimizing reconstructed sagittal balance. The correctly oriented pelvis can be determined before surgery. Preventing junctional fracture and persistent rehabilitation of surgically injured lumbar extensor musculature are crucial for maintaining the reconstructed sagittal balance.


Assuntos
Interpretação de Imagem Assistida por Computador/normas , Equilíbrio Postural , Transtornos de Sensação/diagnóstico por imagem , Transtornos de Sensação/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Região Lombossacral/diagnóstico por imagem , Região Lombossacral/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Controle de Qualidade , Radiografia
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